1. Field of the Invention
The present invention relates to an information processing apparatus, an information processing method, and program therefor, and in particular relates to a technique to assign metadata to target data.
2. Description of the Related Art
The proliferation of digital cameras and digital video recorders has dramatically increased the number of still images and moving images managed by users. To manage such a large amount of image data, information that explains images, such as names of events and shooting places at the time of shooting, is used, which is known as metadata. For example, a user inputs an event name or the like of image data to be found, and the desired image data is looked for based on the event name or the like.
Conventionally, in order to assign such metadata, a configuration is known in which information related to images is estimated using information obtained from external resources (Japanese Patent Laid-Open No. 2005-149511). In this configuration, information available from external resources is identified using metadata that represents the status at the time of shooting, such as shooting dates and times or shooting positions. In cases where external resources provide systematically managed information such as National Weather Service, metadata will be determined with high precision.
However, in cases where image data pieces to which the names of shooting places, for example, have been previously assigned are collected and used as external resources, metadata is not always determined with high precision. For example, data such as the names of shooting places may have a hierarchy. Thus, different metadata values may be assigned to the same shooting place. In addition, indiscriminate use of a common metadata estimation method, irrespective of the distribution of case data pieces relative to an estimation target data piece, does not always determine optimum metadata with high precision. Therefore, it is insufficient to only identify those data pieces that have similar metadata that represents the status at the time of shooting.